Year annual % 1961 2.9919022548593284 1962 3.0153976563773806 1963 3.0074730419363807 1964 2.9889707495648956 1965 3.6983005019020245 1966 3.32447408581071 1967 2.9591723303894466 1968 4.640599867474656 1969 4.556380230265683 1970 4.678971024799676 1971 10.735075596144494 1972 10.656704330168559 1973 10.46165602608351 1974 10.332918076015654 1975 10.273054458594922 1976 10.186995542455648 1977 9.96006050571611 1978 7.733995865887448 1979 5.674417769226146 1980 5.735565012725421 1981 5.756870814480904 1982 5.703832051013097 1983 5.577741651893994 1984 5.6095317984541495 1985 5.3300536981902775 1986 3.8383467072967195 1987 3.809132137852246 1988 3.6306968675336746 1989 3.4661502140670652 1990 3.301865046086231 1991 2.8992943552614747 1992 2.720067472953579 1993 2.518078221977571 1994 2.306015888505975 1995 2.556611895767606 1996 3.5918680341615343 1997 3.3673215106587806 1998 3.167560137788191 1999 2.9709615993340934 2000 3.65346941142273 2001 5.768706365582629 2002 5.728838498519746 2003 5.6252619256650265 2004 5.5234317448640935 2005 5.408116132482448 2006 5.422619187247686 2007 4.513871781881762 2008 4.710607738826832 2009 4.692119189359394 2010 4.668703024905988 2011 4.628708468440797 2012 4.566641303425131 2013 4.461913011456399 2014 5.028559544324311 2015 5.526362663265106 2016 5.2939785636757835 2017 5.014314947483766 2018 4.680509203400014 2019 4.041588631074411 2020 3.0146307558326058 2021 2.4140226796253903 2022 1.496245691902483 2023 0.512565364642184